This file shows changes made to the Miduss98 executable since the release of Version 1 on Sept. 4, 1998.

  • Aug. 13,‘03
    Unfortunately, the ‘improvement’ in the Storm and Catchment commands of Aug.3 failed for non-Malaysian users when the new Value Key for the Storm and other options had not yet been created. This has been corrected.
  • Aug. 3,’03
    The Storm and Catchment commands have been improved so that user-selected options for storm type, overland routing, length option and infiltration option are stored in the Registry and become the default values for future runs until subsequently changed. For Malaysian users, the Storms (Malaysia) menu item is automatically selected.
  • July 31, ‘02
    The Pond command has been modified to enable routing when all data for WL, Q and Volume has been entered by hand into the HQV grid rather than by use of the Geometry or Outflow Control tools.
  • July 8, ‘03
    In the Pond command the tool to compute the equivalent rectangular aspect ratio as a function of user defined values of area and perimeter has had some cosmetic changes to correct text labels.
  • June 17, ‘03
    In the Pond command an error can occur if one or more weirs are defined but the vector of water levels does not contain a value acceptably close to the weir crest level. This is often caused by using a small number of stages (e.g. less than 10). This has been corrected by warning the user if this situation occurs and prompting a manual edit of the closest water level to match the weir invert level.
  • June 9, ‘03
    The Trench command has been modified to allow a zero value for the gradient. This is useful when modelling an infiltration basin which is approximated by a very wide channel with flat side-slopes and a ‘Voids Ratio’ of 100%.
  • May 28, ‘03
    In the Pond command the [Route] button was not enabled if values of H and V were entered directly into the grid followed by use of the Outflow Control command to define the Q values. This has now been corrected.
  • Apr.11, ‘03
    Minor changes were made to ensure compatibility with controls delivered with Windows XP.
  • Mar.27, ‘03
    An error introduced in the March12, ’03 version caused the Pipe parameters to be overwritten when running in Automatic mode. This has been corrected.
  • Mar.11, ’03
    A number of minor fixes have been made to both the Miduss98.exe program and the Setup.exe files to correct problems with installation and running under Windows NT4, 2000 and XP.
  • Feb. 17, ’03
    In the Pipe command feasible values of Diameter and Grade are shown automatically but can be edited as before or selected from the table of diameters and grades simply by double clicking on a row.
  • Feb.11, ’03
    Some minor changes have been made to detect use of Windows XP and make minor adjustments to dimensions of forms and default positions of the mouse pointer
  • Jan. 11, ’03
    The Hydrology/Baseflow command now includes the option to use a negative value of baseflow.
  • Jan. 1, ’03
    In the Hydrology/Lag & Route command an error in the calculation of the routed hydrograph has been corrected.
  • Dec. 1, ’02
    A minor error has been fixed in the Trench command concerning the adjusting of the stage-volume data to allow for either perforated or non-perforated pipes within the clear stone fill. Previously this occasionally caused the curve of volume as a function of depth to be non-monotonic.
  • Nov. 30, ’02
    In the Hydrograph/Combine command the code has been modified so that in Automatic mode the user can manually define a Junction node prior to the point in the Input database at which the same Junction node is introduced. Subsequent uses of Combine with reference to that Junction node cause flows to be accumulated in the normal way.
  • Nov. 19, ’02
    In the Hydrology/Storm command the Canadian AES option gave an error if the storm duration was less than or equal to the time to peak. This error is now properly trapped and corrected.
  • Nov. 12, ’02
    In the Hydrology/Lag and Route command, any change made to the values of channel or reservoir lag did not cause the [Accept] button to be disabled (grayed out). This has now been corrected thus forcing the user to press the [Route] button to update the result before accepting the result.
  • Nov. 8, ’02
    In the Channel command the format of the value of Manning’s ‘n’ has been changed to show 3 decimal figures. This corrects a problem in which a value of (say) n = 0.036 used in Manual mode was read in Automatic mode as n = 0.04 with resultant change in the computed design results.
  • Oct. 22, 2002
    When using the Show/Output File command MIDUSS uses Wordpad.exe if the Output File is larger than 50 KB. If Wordpad.exe is not found either by the program or by the user the Show/Output File is cancelled. Previously this sometimes caused the Output File to be closed, which effectively terminated the session. This problem has now been corrected.
  • Oct. 21, 2002
    Correction made in the Form that displays graphics to update status of the window.
    When running in Manual mode use of the Hydrograph/Undo command is sometimes necessary to correct an error. This is saved in the Output file. Code has been changed in the routine that converts an Output file to database Miduss.Mdb so that if the ‘HYDROGRAPH Undo’ record is encountered the user is warned of the location and advised to check if use of ‘Undo’ is still appropriate in a subsequent run in Automatic mode.
    Code in the graphic display module has been corrected to avoid an error resulting in a “Log of zero variable” warning that occurred in certain rare circumstances.
    In graphic displays the user selected time window for a hydrograph is now saved as the default for the next hydrograph graphic display. Also, the selected time window in the graphic display is now properly rounded down to the nearest 50 or 100 minutes instead of the nearest time increment.
    In the Hydrology/Lag & Route command the user choices for ‘Show Options’ and ‘Set Lags Explicitly’ are now retained as defaults for the next use of the command.
  • Sept. 10, 2002
    A display error in the Lag & Route command has been fixed. When the lag & route operation is carried out the modified Runoff hydrograph is displayed in a table. This table contains a spin button to change the number of decimal places used. Unfortunately, in this command use of the spin button caused a different hydrograph to be displayed. The graph display and the computed (and saved) result was unaffected.
  • Sept. 9, 2002
    In the Trench command the user can define the diameter of the upstream manhole access shaft. This affects the stage-volume curve and in certain cases may help to avoid numerical instabilities. The command has been modified so that a finite value is initially displayed as the default. Previously, the default was zero.
  • Sept. 8, 2002
    When an existing output file is processed to create the input database Miduss.Mdb the path of the old file was sometimes truncated if very long. This has been corrected.
  • March 30, 2002
    Two problems corrected concerning the use of the Hydrograph/Undo command immediately after the Hydrograph/Combine command and after the Hydrograph/Confluence command.
    After the Combine command the Undo command correctly updates the junction file.
    After the Confluence command the Undo command writes the appropriate code to the Output file.
  • March 27, 2002
    The Show/Output File command has been further corrected to display large Output files in Wordpad when the Output file resides in a folder which has a path with one or more spaces.
  • March 24, 2002
    The command Show/Output File uses either Notepad or Wordpad to display the output file. Users have reported that Wordpad sometimes reports a file sharing error. This has been corrected.
  • March 17,2002
    In the Edit Inflow command the user is prompted to provide a brief description of the modified hydrograph when it is Accepted and saved. An error has been corrected which prevented this new description from being included in the header of the file.
  • February 28, 2002
    On October 30, 2001 an improvement to the Pond command was added which automatically extended the range of depth was added. The messages associated with this feature have been improved to advise the user how to reject this automatic procedure if required.
  • February 19, 2002
    In the POND command the superpipe storage device may be surcharged under extreme peak inflows. Previously this resulted in a vertical segment in the volume-stage curve which resulted in incorrect solutions. The calculation of volume has been modified to add to the volume the contribution of an upstream MH (1.2 m or 4 ft diam.) for each superpipe when the water level is higher than the upstream obvert level. This has improved the solution. Problem identified by Gustavo Jacome, R.V.Anderson Ltd.
  • February 18, 2002
    In the Catchment command the SCS Curve Number option for rainfall loss estimation uses the parameters of Curve Number (CN), Runoff coeff. (C), Initial abstraction to potential Storage (Ia/S) and Initial abstraction depth (Ia). These are interdependent and changing any one will alter one or more of the other three. A coding error which made it difficult to explicitly define Ia has been corrected.
    If an unusual value is entered for any of the Catchment parameters a warning message alerts the user to a possible error. The message text gave a wrong description when metric (SI) units were used and this has now been corrected.
    The calculation of the runoff hydrograph remains unchanged and involves the summation of the direct runoff from pervious and impervious fractions of the catchment area.
  • January 19, 2002
    In the POND command if the user checks the ‘Keep all design data’ checkbox the [Route] button is enabled and the Peak Outflow is set to a blank when POND is used for a second time in the same design session.
    When running in Automatic mode, the Combine command now shows the [New] button as enabled in order to let the user add a new junction without having to revert to Manual mode and then re-invoke Automatic mode.
  • December 17, 2001
    A number of changes have been made to the messages displayed when transferring a license to another computer in order to prevent users from making errors in this process.
  • December 13, 2001
    Corrections have been made to the commands for Automatic design of Pipes and Channels which are surcharged.
  • December 4, 2001
    The logic and informational messages for the design of surcharged pipes and overtopped channels has been improved to clarify the various steps for both Manual and Automatic processing. Where possible the mouse pointer is automatically positioned on the response buttons of message boxes to speed processing in Automatic mode. These changes are an improvement on the update of November 19.
  • December 1, 2001
    The change reported on November 25 has been modified. After creating or editing an Inflow hydrograph the user presses the [Accept] button and is forced to save the hydrograph as a file by specifying a filename in a Common Dialogue box. In addition, the user can enter a brief description of the file which forms part of the file header. Records are written to the Output file containing the description, filename, peak flow, duration and volume. In Automatic mode this information allows the file to be retrieved and loaded into the Inflow hydrograph if the user wishes to do so.
  • November 25, 2001
    When the ‘Hydrograph/Create/Edit Inflow hydrograph’ command is used the new hydrograph is not automatically saved (see Help file). The [Accept] button has been modified to check if the user has saved the hydrograph as a file. If not already saved a warning message is displayed and an opportunity is given to open and use the ‘Hydrograph/FileI_O’ command.
  • November 19, 2001
    When using the ‘Design/Pipe’ command in Automatic mode the program logic and warning messages have been improved to assist the user in handling the case of a surcharged pipe. Appropriate action is taken depending on the use or absence of the Diversion command in the Input database file. Similarly, the program checks for the use of the ‘Hydrograph/Next Link’ command after the Diversion command before using the Route command.
    Corresponding changes have been made for using MIDUSS in Manual mode.
  • November 15, 2001
    When processing a complex Channel cross-section in Automatic mode, the vertical and horizontal scales are now given more reasonable values to display the cross-section.
  • November 9, 2001
    The Trench command has been improved to indicate surcharged conditions by regular Message boxes instead of the “red box” in the Trench window.
    An error occurs in the Catchment command if the storm duration is less than three times the time step. This condition is checked and if detected the user is advised to reduce the time step. The error is normally handled well by the FailSafe version of MIDUSS
  • November 6, 2001
    The Hydrograph Menu has been modified to show the commands ‘Start New Tributary’ and ‘Create/Edit Inflow hydrograph’ instead of having these below the ‘Start’ menu.
    The ‘Create/Edit Inflow hydrograph’ command has been modified to compute the Inflow volume. Previously this was undefined and caused an error if the Design/Pond command was attempted with the new Inflow hydrograph.
  • November 4, 2001
    The use of the Channel and Pipe commands in Automatic mode has been modified to ensure that a false “surcharged/overtopped” error is not displayed when the inflow is increased significantly between successive uses of the Channel or Pipe command in the input database. This was caused by the Channel or Pipe window being displayed before all of the relevant data had been read from the input database Miduss.Mdb.
  • November 1, 2001
    The command Hydrograph/FileI_O was modified to correct an error when writing a hydrograph to a file. Previously, the list of elements was repeated making the file twice as long as required. No numerical error was caused because only the first set of records was processed when the file was imported.
  • October 30,2001
    The Design/Pond command has been improved to automatically extend the range (i.e. increase the maximum water level) in order to process the Inflow hydrograph. Error reporting if zero elements or non-monotonic functions are detected now uses regular Message boxes instead of the “red box” message in the Pond window.
    The Trench command has been similarly modified.
  • October 10,2001
    In the AuthorizationInfo and Authorization windows the ‘What’s This’ Help did not work properly. This feature has therefore been disabled and the Authorization form is now directly linked to the regular Help file. A short Help file has also been added to the form describing the steps for transferring a license from one computer to another.
  • Appendix ‘B’ in the Help file has been completely re-written with many more illustrations. The topics have been expanded to cover Installation and Licensing of MIDUSS plus the license transfer procedure.
  • The messages displayed in the license transfer process have been improved.
  • October 2, 2001
    If Miduss was closed abnormally the next session showed a warning message that the Design.log file was about to be deleted. The message has been made more explicit to inform users of the reason.
  • September 23, 2001
    A correction has been made to the Show/Restore Peak Flow Table that was not operating correctly in recent versions.
    The File/Output File menu item has been changed so that the secondary menu items Create New File and Open Existing file have been deleted and combined into the single File/Open Output file command. The functionality has not changed but since the ‘Create New file’ and ‘Open Exiting file’ performed the same operation confusion over these items is now avoided.
    In the Automatic Control Panel the [CLOSE] button is now disabled until an EXIT command has been read and processed in the input database Miduss.Mdb. This avoids an error condition encountered by attempting to close the file prematurely. More importantly, it is now possible to [SKIP] forward to and process the EXIT command and then press the [CLOSE] button following which a new input database file Miduss.Mdb can be created and opened to continue the run in Automatic mode. This allows two or more Input files to be combined in a single run.
  • September 16, 2001
    In Route command code corrected to display channel depth for trapezoidal or complex cross-sections
  • September 5, 2001
    Pond command modified to estimate time to centroid if last ordinate in outflow hydrograph is finite
  • In Channel command code corrected to allow extra point to be added in table of coordinates
  • July 12, 2001
    In Catchment command rainfall loss parameters in SCS method made more interactive so that change in one causes related parameters to be updated.
  • June 22, 2001

Time of Concentration tool modified to allow choice between Friend eq. And Kinematic Wave eq. for overland flow time. Tool can be used for both Metric and U.S.Customary units.